Structure and Conductivity in LISICON Analogues within the Li4GeO4-Li2MoO4 System.

New solid electrolytes are crucial for the development of all-solid-state lithium batteries with advantages in safety and energy densities over current liquid electrolyte systems. While some of the best solid-state Li+-ion conductors are based on sulfides, their air sensitivity makes them less commercially attractive, and attention is refocusing on air-stable oxide-based systems. Among these, the LISICON-structured systems, such as Li2+2xZn1-xGeO4 and Li3+xV1-xGexO4, have been relatively well studied. However, other systems such as the Li4GeO4-Li2MoO4 system, which also show LISICON-type structures, have been relatively little explored. In this work, the Li4-2xGe1-xMoxO4 solid solution is investigated systematically, including the solid solution limit, structural stability, local structure, and the corresponding electrical behavior. It is found that a γ-LISICON structured solution is formed in the range of 0.1 ≤ x < 0.4, differing in structure from the two end members, Li4GeO4 and Li2MoO4. With increasing Mo content, the ß-phase becomes increasingly more stable than the γ-phase, and at x = 0.5, a pure ß-phase (ß-Li3Ge0.5Mo0.5O4) is readily isolated. The structure of this previously unknown compound is presented, along with details of the defect structure of Li3.6Ge0.8Mo0.2O4 (x = 0.2) based on neutron diffraction data. Two basic types of defects are identified in Li3.6Ge0.8Mo0.2O4 involving interstitial Li+-ions in octahedral sites, with evidence for these coming together to form larger defect clusters. The x = 0.2 composition shows the highest conductivity of the series, with values of 1.11 × 10-7 S cm-1 at room temperature rising to 5.02 × 10-3 S cm-1 at 250 °C.

Local Structure in α-BIMEVOXes (ME = Ge, Sn).

The BIMEVOXes are among the best oxide ion conductors at low and intermediate temperatures. Their high conductivity is associated with local defect structure. In this work, the local structures of two BIMEVOX compositions, Bi2V0.9Ge0.1O5.45 and Bi2V0.95Sn0.05O5.475, are examined using total neutron and X-ray scattering methods, with both compositions exhibiting the ordered α-phase at 25 °C and the disordered γ-phase at 700 °C. While the diffraction data for the α-phase do not allow for the polar (C2) and nonpolar (C2/m) structures to be readily distinguished, measurements of dielectric permittivity suggest the α-phase is weakly ferroelectric in character, consistent with calculations of spontaneous polarization based on a combination of density functional calculations and machine learning methodology. Reverse Monte Carlo (RMC) analysis of total scattering data reveals Ge preferentially adopts tetrahedral geometry at both temperatures, while Sn is found to predominantly adopt octahedral coordination in the α-phase and tetrahedral coordination in the γ-phase. In all cases, V polyhedra are found to consist of tetrahedral, pentacoordinate, and octahedral geometries, as also predicted by the crystallographic analysis and confirmed by 51V solid state NMR spectroscopy. Although similar long-range structures are observed at room temperature, the oxide ion vacancy distributions were found to be quite different between the two studied compositions, with a nonrandom deficiency in vacancy pairs in the second-nearest shell along the ⟨100⟩ tetragonal direction for BIGEVOX10, compared with a long-distance (>8.0 Å) ordering of equatorial vacancies for BISNVOX05. This is attributed to the differences in the preferred coordination geometries of the substituent cations in the two systems. Impedance spectroscopy measurements reveal both compositions show high conductivity in the order of 10-1 S cm-1 at 600 °C.

Under the influence of nature: The contribution of natural capital to tourism spend.

Tourism and outdoor leisure is an important economic sector for many countries, and has a substantial reliance on natural capital. Natural capital may be the primary purpose for tourism, or it may be a secondary factor, where the choice of location for a leisure activity is influenced by natural capital. Typically, when valuing tourism and outdoor leisure, all expenditure associated with the activity is assigned to the ecosystem it occurs in. However, this value illustrates the dependency on natural capital, rather than the contribution of natural capital. In natural capital accounting, a major challenge is to separately identify the contribution of natural capital from that of other forms of capital. In this study we develop a transparent and repeatable method that is able to attribute the contribution of natural capital (here defined as ecosystems) to the output of multiple tourism and outdoor leisure activities. Using national statistics from Great Britain, we calculate the natural capital contribution to tourism spend by activity at a national and regional scale, and for a case study map and value the contributing ecosystems. We estimated that, out of a total £36 billion spent on tourism and leisure activities in 2017, £22.5 billion was attributable to natural capital. This equates to 0.9% of the UK GDP. The Gross Value Added component of this attributable was £10.5 billion, equivalent to 0.4% of the UK GDP. Regions with the highest natural capital contribution in Great Britain were Scotland and Wales, with the lowest being Greater London and the West Midlands in England. For the case study, the ecosystems with the greatest contribution to terrestrial activities were marine and enclosed farmland. These methods can be applied worldwide for anywhere with aggregate economic statistics on expenditure associated with tourism and outdoor leisure, with the aid of open source GIS datasets.

Phase behaviour of ammonium bromide-d4under high pressure and low temperature; an average and local structure study.

We revisit the pressure-induced order-disorder transition between phases II and IV in ammonium bromide-d4using neutron diffraction measurements to characterise both the average and local structures. We identify a very sluggish transition that does not proceed to full conversion and local structure correlations indicate a slight preference for ammonium cation ordering along ⟨110⟩ crystallographic directions, as pressure is increased. Simultaneous cooling below ambient temperature appears to facilitate the pressure-induced transition. Variable-temperature, ambient-pressure measurements across the IV → III → II transitions show slower conversion than previously observed, and that phase III exhibits metastability above ambient temperature.

Bright spots as climate-smart marine spatial planning tools for conservation and blue growth.

Marine spatial planning that addresses ocean climate-driven change ('climate-smart MSP') is a global aspiration to support economic growth, food security and ecosystem sustainability. Ocean climate change ('CC') modelling may become a key decision-support tool for MSP, but traditional modelling analysis and communication challenges prevent their broad uptake. We employed MSP-specific ocean climate modelling analyses to inform a real-life MSP process; addressing how nature conservation and fisheries could be adapted to CC. We found that the currently planned distribution of these activities may become unsustainable during the policy's implementation due to CC, leading to a shortfall in its sustainability and blue growth targets. Significant, climate-driven ecosystem-level shifts in ocean components underpinning designated sites and fishing activity were estimated, reflecting different magnitudes of shifts in benthic versus pelagic, and inshore versus offshore habitats. Supporting adaptation, we then identified: CC refugia (areas where the ecosystem remains within the boundaries of its present state); CC hotspots (where climate drives the ecosystem towards a new state, inconsistent with each sectors' present use distribution); and for the first time, identified bright spots (areas where oceanographic processes drive range expansion opportunities that may support sustainable growth in the medium term). We thus create the means to: identify where sector-relevant ecosystem change is attributable to CC; incorporate resilient delivery of conservation and sustainable ecosystem management aims into MSP; and to harness opportunities for blue growth where they exist. Capturing CC bright spots alongside refugia within protected areas may present important opportunities to meet sustainability targets while helping support the fishing sector in a changing climate. By capitalizing on the natural distribution of climate resilience within ocean ecosystems, such climate-adaptive spatial management strategies could be seen as nature-based solutions to limit the impact of CC on ocean ecosystems and dependent blue economy sectors, paving the way for climate-smart MSP.

Effectiveness of Educating Health Care Professionals in Managing Chronic Pain Patients Through a Supervised Student Inter-professional Pain Clinic.

OBJECTIVE: To address the need for increased and more effective medical education regarding chronic pain and pain management, an inter-professional (IP) training program in the form of a supervised student IP pain clinic was implemented in 2016. In the current study, we evaluated its feasibility and effectiveness in improving health care professional students' skills in (1) managing chronic pain and (2) working in an IP team. METHODS: From January 2016 to December 2018, we assembled 12 IP teams that included students from the following six professions at the University of New England: nursing, osteopathic medicine (OM), occupational therapy (OT), pharmacy, physical therapy (PT), and social work (SW). During this 12-week training program, each team conducted the initial evaluation, generated treatment plans, and performed follow-up examinations for its assigned patient under the supervision of a pain specialist at the Mercy Pain Center. Surveys were conducted with all participating students and patients. RESULTS: Overall, students showed significant improvement in knowledge regarding pain physiology and chronic pain management as well as attitude and perception regarding IP practice and perceived team skills. Specifically, prior to the program, nursing students showed the greatest pain-related knowledge and perceived team skills, while OT students scored the highest in attitude and perception regarding IP practice. Following the program, improvement in various measures was observed in all professions with PT students showing the most significant improvement in all areas. Surveys also indicated patients' satisfaction with their IP pain clinic experience. CONCLUSIONS: These results demonstrated the feasibility and the effectiveness of this IP training program for all participating professions.

Improving patient-provider communication about chronic pain: development and feasibility testing of a shared decision-making tool.

BACKGROUND: Chronic pain has emerged as a disease in itself, affecting a growing number of people. Effective patient-provider communication is central to good pain management because pain can only be understood from the patient's perspective. We aimed to develop a user-centered tool to improve patient-provider communication about chronic pain and assess its feasibility in real-world settings in preparation for further evaluation and distribution. METHODS: To identify and prioritize patient treatment goals for chronic pain, strategies to improve patient-provider communication about chronic pain, and facilitate implementation of the tool, we conducted nominal group technique meetings and card sorting with patients with chronic pain and experienced providers (n = 12). These findings informed the design of the PainAPP tool. Usability and beta-testing with patients (n = 38) and their providers refined the tool and assessed its feasibility, acceptability, and preliminary impact. RESULTS: Formative work revealed that patients felt neither respected nor trusted by their providers and focused on transforming providers' negative attitudes towards them, whereas providers focused on gathering patient information. PainAPP incorporated areas prioritized by patients and providers: assessing patient treatment goals and preferences, functional abilities and pain, and providing patients tailored education and an overall summary that patients can share with providers. Beta-testing involved 38 patients and their providers. Half of PainAPP users shared their summaries with their providers. Patients rated PainAPP highly in all areas. All users would recommend it to others with chronic pain; nearly all trusted the information and said it helped them think about my treatment goals (94%), understand my chronic pain (82%), make the most of my next doctor's visit (82%), and not want to use opioids (73%). Beta-testing revealed challenges delivering the tool and summary report to patients and providers in a timely manner and obtaining provider feedback. CONCLUSIONS: PainAPP appears feasible for use, but further adaptation and testing is needed to assess its impact on patients and providers. TRIAL REGISTRATION: This study was approved by the University of New England Independent Review Board for the Protection of Human Subjects in Research (012616-019) and was registered with ClinicalTrials.gov (protocol ID: NCT03425266) prior to enrollment. The trial was prospectively registered and was approved on February 7, 2018.

Evaluation of Using the Sphygmomanometer Test to Assess Pain Sensitivity in Chronic Pain Patients vs Normal Controls.

OBJECTIVES: Objectively measuring pain sensitivity has not been easy in primary care clinics. A sphygmomanometer test (a sensory test that measures an individual's nociceptive response to pressure using a standard blood pressure cuff) has recently been established to test pain sensitivity. Here, we examined the feasibility of using the sphygmomanometer test with chronic pain patients. DESIGN: Population, observational study. SETTINGS: A community hospital multidisciplinary Pain Center and a private nonprofit university. SUBJECTS: Healthy controls and chronic pain patients were recruited. METHODS: All subjects underwent four pain sensitivity tests: a pressure algometer test, a cold pressure test, a heat sensitivity test, and a sphygmomanometer test. Participants then completed four established surveys for evaluating depression (Patient Health Questionnaire-9), anxiety (General Anxiety Disorder-7), fatigue (Fatigue Severity Scale), and pain catastrophizing (Pain Catastrophizing Scale). RESULTS: Although pain patients had significantly higher levels of depression, anxiety, fatigue, and pain catastrophizing, as well as reported pain scores, no significant differences in pain sensitivity were detected via any of the pain sensitivity tests. In the control but not the patient group, results from all pain sensitivity tests including the sphygmomanometer test were significantly correlated with each other. Unlike other pain sensitivity tests, the sphygmomanometer test did not correlate with measures of depression, anxiety, fatigue, or pain catastrophizing characteristics. CONCLUSIONS: Our results indicate the unique characteristics of the sphygmomanometer test as a pain sensitivity test, particularly when utilized for individuals with chronic pain. Multiple pain sensitivity tests that assess various sensory modalities are needed to evaluate pain sensitivities in chronic pain patients.

Cost Analysis of Dual-Mobility Constructs in Revision Total Hip Arthroplasty: A European Payer Perspective.

Dual-mobility constructs have been shown to significantly and substantially decrease dislocations after revision total hip arthroplasty (THA). The authors have previously shown that dual-mobility (DM) constructs are cost-effective given their ability to decrease dislocations and re-revision for dislocation. The goal was to report the costs of DM and large femoral head (LFH) constructs in revision THAs from a European health care payer perspective. A Markov model was constructed to analyze the costs incurred by payers in the United Kingdom, Germany, Italy, and Spain over 3 years in revision THAs with DM or LFH constructs. Model states and probabilities were derived from prospectively collected registry data in 302 patients who underwent revision THA with a DM or 40-mm LFH construct and were then mapped to corresponding procedural reimbursement codes and tariffs for each country. Costs were weighted average national payments for reintervention procedures performed in the 3 years following revision THA. Probabilistic sensitivity analysis examined the effect of combined uncertainty across all model parameters. During a 3-year period following revision THA, reintervention rates were 9% for DM constructs and 19% for LFH constructs (P=.01). Comparing DM and LFH constructs, cumulative incremental costs over 3-years' follow-up were £428 vs £1447 in the United Kingdom, euro 451 vs euro 1272 in Germany, euro 540 vs euro 1425 in Italy, and euro 523 vs euro 1562 in Spain, respectively. At mid-term follow-up, DM constructs used in revision THAs were associated with a significantly lower risk of reintervention, which translated to lower health care payer costs compared with LFH constructs among European health care payers. [Orthopedics. 2020;43(4):250-255.].

Combatting Sedentary Lifestyles: Can Exercise Prescription in the Emergency Department Lead to Behavioral Change in Patients?

Introduction Emergency department (ED) patients with chronic disease are known to benefit from exercise; however, there are few studies examining the prescription of exercise in the ED. We asked, is exercise prescription in the ED feasible and effective? Methods In this pilot prospective block randomized trial, consented patients were divided into control and intervention groups. The control group received routine care. The intervention group received combined written and verbal prescriptions for moderate exercise of 150 minutes/week. Both groups were followed up by phone at two months. The primary outcome was achieving 150 minutes of exercise per week. Secondary outcomes included change in exercise and differences in reported median weekly exercise. Results Follow-up was completed for 23/28 patients (11 control; 12 intervention). Baseline reported median (with interquartile range) weekly exercise was similar between groups: control 0 (0-0) minutes, intervention 0 (0-45) minutes. There was no difference between groups for the primary outcome at two months (control 3/11; intervention 4/12, relative risk [RR] 1.33 (95% confidence interval [CI] 0.38-4.6; p=1.0). There was a significant increase in median exercise from baseline in both groups, but no difference between the groups (control 75 (10-225) minutes; intervention 120 (52.5-150) minutes; NS). A post hoc comparison of patients actually receiving intervention vs. no intervention revealed a significant increase in patients meeting the primary outcome (no intervention 0/8; intervention 7/15, RR 2.0 (95% CI 1.2-3.4); p=0.05). Conclusion The improvement seen in patients receiving the exercise prescription intervention, and the increase in reported exercise in both groups suggests that exercise prescription for ED patients may be beneficial.

Defect structure in δ-Bi5PbY2O11.5.

A detailed study of the defect structure in a di-substituted δ-Bi2O3 type phase, δ-Bi5PbY2O11.5, is presented. Using a combination of conventional Rietveld analysis of neutron diffraction data, reverse Monte Carlo (RMC) analysis of total neutron scattering data and ab initio molecular dynamics (MD) simulations, both average and local structures have been characterized. δ-Bi5PbY2O11.5 represents a model system for the highly conducting δ-Bi2O3 type phases, in which there is a higher nominal vacancy concentration than in the unsubstituted parent compound. Uniquely, the methodology developed in this study has afforded the opportunity to study both oxide-ion vacancy ordering as well as specific cation-cation interactions. Oxide-ion vacancies in this system have been found to show a preference for association with Pb2+ cations, with some evidence for clustering of these cations. The system shows a non-random distribution of vacancy pair alignments, with a preference for 〈100〉 ordering, the extent of which shows thermal variation. MD simulations indicate a predominance of oxide-ion jumps in the 〈100〉 direction.

Phase Formation, Crystallography, and Ionic Conductivity of Lithium Manganese Orthosilicates.

On the orthosilicate join, Li4SiO4-Mn2SiO4, the new phase Li3Mn0.5SiO4 and a range of Li2+2 xMn1- xSiO4 solid solutions with ∼0.76 ≤ x ≤ 1 have been prepared by high-temperature, solid-state reaction and characterized. Li3Mn0.5SiO4 is orthorhombic, space group Pnma, with a = 10.722(3) Å, b = 6.239(2) Å, and c = 5.052(3) Å. A combined analysis of X-ray and neutron powder diffraction data show that its structure is derived from the γII tetrahedral structural family typified by Li3PO4, but with additional Li+ in partially occupied, distorted octahedral sites. These octahedral sites are linked by a combination of edge- and face-sharing, similar to that in the nickel arsenide structure and their partial occupancy is responsible for an Li+ ion conductivity of, for example, ∼ 1 × 10-8 S cm-1 at 60 °C, with activation energy 0.93(1) eV, which is many orders of magnitude higher than that of Li2MnSiO4.

The Fluorite-Like Phase Nd5Mo3O16±Î´ in the MoO3-Nd2O3 System: Synthesis, Crystal Structure, and Conducting Properties.

This paper describes a study of the system MoO3-Nd2O3 using a combination of X-ray powder diffraction (XRD), neutron powder diffraction (NPD), thermogravimetric analysis (TGA), and ac impedance spectroscopy (IS). A phase-pure material is observed at a composition of 45.5 mol % Nd2O3, which corresponds to an ideal stoichiometry of Nd5Mo3O16.5. XRD and NPD show that the crystal structure is a superstructure of the fluorite arrangement, with long-range ordering of the two cation species leading to a doubled unit cell parameter. The sample is found to be significantly oxygen deficient, i.e. Nd5Mo3O15.63(4), when it is prepared by a solid-state reaction at 1473 K in air. TGA measurements indicate that the sample loses only minimal mass on heating to 1273 K in O2. IS studies of the mean conductivity under different atmospheres show that the sample is a mixed conductor between ambient temperature and 873 K, with a dominant electronic component at higher temperatures, as demonstrated by measurements under inert atmosphere. NPD measurements indicate that the anion vacancies are preferentially located on the O2 sites, while studies of the temperature dependence performed under an O2 atmosphere to 1273 K show significantly anisotropic thermal parameters of the anions. Together with analysis of the total neutron scattering data, this supports a model of oxygen ions hopping between O2 positions, with a vacancy, rather than interstitial, mechanism for the anion diffusion.

Sexually Transmitted Infections: Compelling Case for an Improved Screening Strategy.

Sexually Transmitted Infections: Compelling Case for an Improved Screening Strategy Stephen Hull, MHS, Seán Kelley, MD, MSc, and Janice L. Clarke, RN, BBA Editorial: Sexually Transmitted Infections-A Fixable Problem: David B. Nash, MD, MBA S-3 Introduction S-3 Rising Prevalence of Sexually Transmitted Diseases (STIs) S-4 Current Screening Rates for Chlamydia and Gonorrhea S-4 The Human Toll and Economic Burden of STI-Related Illness S-5 Current Screening Guidelines for Chlamydia and Gonorrhea S-5 Factors Contributing to Inadequate Screening, Diagnosis, and Treatment for STIs S-6 Methods Used to Improve Screening Rates S-7 Benefits of Opt-Out Screening Strategies for STIs S-8 Cost-Effectiveness of Screening for STIs S-8 Discussion S-9 Conclusion S-10.

Investigation of Antisite Defect Formation and Chemical Expansion in LiNiPO4 by in Situ Neutron Diffraction.

In situ neutron diffraction was used to characterize the effect of temperature on the crystal structure of LiNiPO4. LiNiPO4 adopts an ordered olivine structure at room temperature, but, with increasing temperature, this work shows that a significant amount of Li and Ni cation exchange occurs, for example, ∼15% at 900 °C. The antisite disorder is detected by residual nuclear densities on the M1 and M2 octahedral sites in the olivine structure using difference Fourier maps and by changes in cation site occupancies, lattice parameters, and mean ⟨M-O⟩ bond distances. The antisite disorder is also responsible for chemical expansion of the crystal lattice in addition to thermal expansion. Antisite defect formation at high temperature and its reversibility on cooling can be understood as an entropically driven feature of the crystal structure of LiNiPO4. The lithium ion diffusion pathway, that follows a curved trajectory along the b axis in the olivine structure, is, therefore, susceptible to be blocked if synthesis conditions are not carefully controlled and should also be influenced by the chemically expanded lattice of the disordered structure if this is preserved to ambient temperature by rapid cooling.

C-type related order in the defective fluorites La2Ce2O7 and Nd2Ce2O7 studied by neutron scattering and ab initio MD simulations.

This work presents a structural investigation of La2-xNdxCe2O7 (x = 0.0, 0.5, 1.0, 1.5, 2.0) using X-ray powder diffraction and total scattering neutron powder diffraction, analysed using Rietveld and the reverse Monte Carlo method (RMC). Ab initio molecular dynamics (MD) modelling is also performed for further investigations of the local order. The main intensities in the neutron diffraction data for the La2-xNdxCe2O7 series correspond to the fluorite structure. However, additional C-type superlattice peaks are visible for x > 0 and increase in intensity with increasing x. The Nd-containing compositions (x > 0) are best fitted with Rietveld analysis by using a combination of oxygen deficient fluorite and oxygen excess C-type structures. No indications of cation order are found in the RMC or Rietveld analysis, and the absence of cation order is supported by the MD modelling. We argue that the superlattice peaks originate from oxygen vacancy ordering and associated shift in the cation position away from the ideal fluorite site similar to that in the C-type structure, which is seen from the Rietveld refinements and the observed ordering in the MD modelling. The vacancies favour alignments in the 〈110〉, 〈111〉 and especially the 〈210〉 direction. Moreover, we find that such ordering might also be found to a small extent in La2Ce2O7, explaining the discernible modulated background between the fluorite peaks. The observed overlap of the main Bragg peaks between the fluorite and C-type phase supports the co-existence of vacancy ordered and more disordered domains. This is further supported by the observed similarity of the radial distribution functions as modelled with MD. The increase in long range oxygen vacancy order with increasing Nd-content in La2-xNdxCe2O7 corresponds well with the lower oxide ion conductivity in Nd2Ce2O7 compared to La2Ce2O7 reported earlier.

Crystal structure and proton conductivity of BaSn0.6Sc0.4O3-δ : insights from neutron powder diffraction and solid-state NMR spectroscopy.

The solid-state synthesis and structural characterisation of perovskite BaSn1-x Sc x O3-δ (x = 0.0, 0.1, 0.2, 0.3, 0.4) and its corresponding hydrated ceramics are reported. Powder and neutron X-ray diffractions reveal the presence of cubic perovskites (space group Pm3m) with an increasing cell parameter as a function of scandium concentration along with some indication of phase segregation. 119Sn and 45Sc solid-state NMR spectroscopy data highlight the existence of oxygen vacancies in the dry materials, and their filling upon hydrothermal treatment with D2O. It also indicates that the Sn4+ and Sc3+ local distribution at the B-site of the perovskite is inhomogeneous and suggests that the oxygen vacancies are located in the scandium dopant coordination shell at low concentrations (x ≤ 0.2) and in the tin coordination shell at high concentrations (x ≥ 0.3). 17O NMR spectra on 17O enriched BaSn1-x Sc x O3-δ materials show the existence of Sn-O-Sn, Sn-O-Sc and Sc-O-Sc bridging oxygen environments. A further room temperature neutron powder diffraction study on deuterated BaSn0.6Sc0.4O3-δ refines the deuteron position at the 24k crystallographic site (x, y, 0) with x = 0.579(3) and y = 0.217(3) which leads to an O-D bond distance of 0.96(1) Å and suggests tilting of the proton towards the next nearest oxygen. Proton conduction was found to dominate in wet argon below 700 °C with total conductivity values in the range 1.8 × 10-4 to 1.1 × 10-3 S cm-1 between 300 and 600 °C. Electron holes govern the conduction process in dry oxidizing conditions, whilst in wet oxygen they compete with protonic defects leading to a wide mixed conduction region in the 200 to 600 °C temperature region, and a suppression of the conductivity at higher temperature.

Proton conductivity of hexagonal and cubic BaTi1-xScxO3-δ (0.1 ≤x≤ 0.8).

BaTi1-xScxO3-δ (x = 0.1-0.8) was prepared via solid state reaction. High resolution X-ray powder diffraction was used to characterise the synthesised materials. It was found that low substitution (x = 0.1 and 0.2) of Ti(4+) for Sc(3+) gives a hexagonal perovskite structure, whereas high substitution (x = 0.5-0.7) results in a cubic perovskite structure. Thermogravimetric analysis revealed significant levels of protons in both as-prepared and hydrated samples. Electrical conductivity was measured by AC impedance methods under oxygen, argon and under dry and humid, both H2O and D2O, conditions for BaTi1-xScxO3-δ (x = 0.2, 0.6 and 0.7). In the temperature range of 150-600 °C, under humid conditions, the conductivity is significantly higher than that under the dry conditions. The increase in conductivity is especially prominent for the cubic phases, indicating that protons are the dominant charge carriers. The proton conductivity of hexagonal BaTi0.8Sc0.2O3-δ is approx. two orders of magnitude lower than that of the more heavily substituted cubic phases. Conductivity is also found to be higher in dry O2 than in Ar in the whole temperature range of 150-1000 °C, characteristic of a significant contribution from p-type charge carriers under oxidising atmospheres. Greater Sc(3+) substitution leads to a higher proton concentration and the highest proton conductivity (σ∼ 2 × 10(-3) S cm(-1) at 600 °C) is found for the BaTi0.3Sc0.7O3-δ composition.

The proton conducting electrolyte BaTi0.5In0.5O2.75: determination of the deuteron site and its local environment.

Deuterated BaTi0.5In0.5O2.75 has been studied with neutron total (Bragg plus diffuse) scattering data, using both the Rietveld refinement method and the reverse Monte Carlo (RMC) modelling technique, to investigate the preferred proton site and its local structural environment. The Rietveld analysis shows an excellent fit between experimental data and a long-range cubic description of the BaTi0.5In0.5O2.53(OD)0.44 perovskite structure containing a statistical distribution of Ti and In ions at the centre of regular (Ti/In)O6 octahedra. However, an RMC analysis of the data reveals substantial local structural features that reflect limitations of the Rietveld method for studies of this type. The Ti-O and In-O pair distribution functions given by the RMC analysis are markedly different from each other, with average Ti-O and In-O bond distances of 2.035 Å and 2.159 Å, respectively. The InO6 octahedra are regular in shape whereas the TiO6 octahedra are distorted. The average O-D bond distance is roughly 0.96 Å, and the preferred deuteron sites have a second nearest oxygen distance of 2.13 Å, which confirms localized tilting of the deuteron and indicates a substantial degree of hydrogen bonding. The impact of octahedral distortion and hydrogen bonding on the proton conduction mechanism is discussed.

Pioglitazone protects HDL(2&3) against oxidation in overweight and obese men.

BACKGROUND: The worldwide epidemic of obesity is a major public health concern and is persuasively linked to the rising prevalence of diabetes and cardiovascular disease. Obesity is often associated with an abnormal lipoprotein profile, which may be partly negated by pioglitazone intervention, as this can influence the composition and oxidation characteristics of low-density lipoprotein (LDL). However, as pioglitazone's impact on these parameters within high-density lipoprotein (HDL), specifically HDL(2&3), is absent from the literature, this study was performed to address this shortcoming. METHODS: Twenty men were randomized to placebo or pioglitazone (30 mg/day) for 12 weeks. HDL(2&3) were isolated by rapid-ultracentrifugation. HDL(2&3)-cholesterol and phospholipid content were assessed by enzymatic assays and apolipoprotein AI (apoAI) content by single-radial immunodiffusion. HDL(2&3) oxidation characteristics were assessed by monitoring conjugated diene production and paraoxonase-1 activity by spectrophotometric assays. RESULTS: Compared with the placebo group, pioglitazone influenced the composition and oxidation potential of HDL(2&3). Specifically, total cholesterol (P < 0.05), phospholipid (P < 0.001) and apoAI (P < 0.001) were enriched within HDL(2). Furthermore, the resistance of HDL(2&3) to oxidation (P < 0.05) and the activity of paroxonase-1 were also increased (P < 0.001). CONCLUSIONS: Overall, these findings indicate that pioglitazone treatment induced antiatherogenic changes within HDL(2&3), which may help reduce the incidence of premature cardiovascular disease linked with obesity.